feat(keycloak): networkPolicy.ingress.ambientMesh

Gitea #143. Additive, default false, so the render is byte-identical to the
previous release - proven by diffing both renders against origin/main rather
than asserted.

Switched on it adds 15008/TCP, ztunnel's HBONE tunnel, to the rule carrying
the probe port, and - inside that rule's source-restricted branch -
169.254.7.127/32, the address the kubelet's probes arrive from once the pod is
in the mesh. Ambient does not bypass NetworkPolicy enforcement, so without the
port a pod whose namespace has joined the mesh is unreachable.

The two halves are one value because the second is the one nobody thinks of:
15008 added by hand leaves a policy that passes review and drops every probe
the first time probeSources is narrowed, and a pod that never becomes Ready
reads as a broken application rather than as a policy.

Minor, not major: additive value, unchanged default, unchanged render.

keycloak/Chart.yaml

@@ -43,7 +43,7 @@ type: application
 # procedure lives in NOTES.txt and on the wiki page instead of in a
 # packageRules entry. Read the "MINOR UPGRADES" section of NOTES.txt before
 # merging an app-version PR that changes the minor.
-version: 2.0.0+up26.8.0
+version: 2.1.0+up26.8.0
 appVersion: "26.8.0"
 
 maintainers: